Preheat Oven: Set the oven to 350°F (175°C). Line baking sheets with parchment paper or silicone mats.
Mix Dry Ingredients: In a medium bowl, whisk together flour, baking soda, baking powder, salt, and espresso powder. Set aside.
Cream Butter and Sugars: In a large mixing bowl or stand mixer, beat the butter, granulated sugar, and brown sugar on medium speed for 2–3 minutes until light and creamy.
Add Eggs and Vanilla: Mix in the eggs one at a time, then add the vanilla extract. Scrape down the sides of the bowl as needed.
Combine Wet and Dry Mixtures: Gradually add the dry ingredients to the butter mixture. Mix on low speed until just combined — do not overmix.
Fold in Chocolate: Gently fold in the chocolate chips or chunks using a spatula.
Chill the Dough: Cover and refrigerate for at least 30 minutes (up to 24 hours) for better flavor and less spread.
Scoop Dough: Use a cookie scoop or tablespoon to form 1½ tablespoon portions. Arrange on baking sheets, spaced 2 inches apart.
Bake: Bake for 10–12 minutes or until edges are golden brown and centers are slightly soft.
Cool: Let cookies rest on the pan for 3–5 minutes, then transfer to a wire rack to cool completely.
Finish (Optional): Sprinkle warm cookies with a pinch of flaky sea salt for a gourmet touch.